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Fishery Bulletin 91(1), 1993 



Figure 3 



Development stages of Aulotrachichthys sp.: (A) 2.9mm, (B) 3.4 mm, (C) 4.4 mm, (D) 4.7 mm, (E) 5.7 mm (note: pectoral fin missingl, 

 (F) 7.9 mm. Arrows indicate location of anus. 



and these develop rapidly. Distinct buds are present 

 by 3.2 mm, and the developing fin reaches up to 25% 

 body length by 6.2mm (Fig. 4A-C). Ossification com- 

 mences by 5.1mm, and a full complement of seven 

 elements is present by 8.0 mm. Anlagen of both dorsal 

 and anal fins are present by 2.7 mm and appear as 

 hyaline zones located within the median finfolds, as in 

 Paratrachichthys. Bases are first visible in both fins 

 by 3.5 mm, and incipient rays are present by 4.0 mm. 

 Incipient rays appear in the pectoral fin by 4.5 mm. 

 Ossification of the dorsal, anal, and pectoral fins com- 

 mences in early-flexion-stage larvae, with a full comple- 

 ment in all fins present by 7.1 mm. 



Spination Head spination is only weakly developed 

 in preflexion Optivus larvae. A low supraocular ridge 

 is present by 2.7 mm, with 4-5 spines developing by 

 3.4mm (Fig. 4A). By 4.5 mm, these supraocular spines 

 have disappeared. Cranial ridges are present by 

 4.7mm, and a series of spines develops on the 

 preopercular margins by 5.1mm. The preopercular, 

 opercular, and posttemporal spines characteristic of 

 adults are present by 23.0 mm ( Fig. 4E ). 



Scalation Small dermal spines appear on the body by 

 4.7 mm and develop in longitudinal rows over the en- 

 tire body and dorsal- and anal-fin bases by 5.1 mm. By 

 8.0 mm the base of each single dermal spine has trans- 



